inorganic- the mineral can't come from an organism crystal- the solid made up of atoms from an inorganic thing element- something made up of one part of electrons, protons, and a nucleus compound- parts of electrons and protons that are stuck together Moh's Hardness Scale- something that puts minerals in places depending on their toughness streak- the color of the particles left by rubbing the inorganic solid against a streak plate luster- something that means how much the inorganic solid shines cleavage- an inorganic organism that breaks in two on something smooth fracture- how a inorganic organism appears when it splits in a weird form fluorescence- an inorganic organism that shines below a super shining light
Outline
Intro
In a museum
find hall of minerals
find minerals like sphalerite
sphalerite makes tin cans and computer chips
What is a Mineral
Many Minerals
more than 3,000
only 100 are common
20 minerals make up the earth's crust
rock forming minerals
To be a mineral it must be...
naturally occurring, inorganic, solid, crystal structure, and a definite chemical composition
Naturally occurring
minerals mus occur naturally
cement, brick, steel are all man made
Inorganic
can't come from parts of a living thing
coal comes from plant remains and animals remains that lived long time ago
Solid
has a definite volume and shape
all materials are packed tightly
Crystal Structure
mineral particles line up in a pattern that repeats
this makes a crystal
crystal has flat sides (faces) that have sharp edges and corners
crystal structure can be noticeable or hard to recognize
few minerals don't have crystal structures but are still minerals
opal
Definite Chemical Composition
minerals contain definite elements
elements are substances composed of a single atom type
almost all elements are compounds
compounds are made of two or more elements
The elements that make th compound are chemically connected
quartz crystal has 1 atom of silicon for every 2 atoms of oxygen
some elements appear as them selfs with nothing else
like copper, silver, god are minerals
Identifying Minerals
1849 - Gold Rush
1,000s of people went west for gold in the California hills
some found gold, some found fools gold
There are so many minerals that identifying them is difficult
each mineral has its own properties
some easy to tell, some hard
7 tests to tell
hardness, color, streak, luster, density, crystal systems, cleavage and fracture
Hardness
scale called Moh's Hardness scale
measures ten mineral's hardness from softest to hardest
a mineral can scratch any mineral softer than itself
to find the hardness of a mineral that isn't on the list, test it by scratching it with minerals that are on the list
such as sphalerite, a 4 on the scale because it can be scratched by Apatite
The Moh's Hardness Scale
Color
easy to identify property
color cannot tell you what many minerals are, but some can
such as malachite (always green), and azurite (always blue)
many minerals come in varieties
Streak
streak is the color of the minerals power
you can observe a streak by rubbing a mineral by a special tile called a streak plate
streak color an mineral color often vary
for example, pyrite has a gold color with a greenish-black streak
real gold makes a golden-yellow streak
Luster
luster is how a mineral's sides reflects light
metal minerals are shiny like galena and unlike the mineral malachite
some like quartz, have a glassy luster
some are earthy, wavy, and pearly
Density
density is the mass in a given space (mass per unit volume)
no matter what the size, the density is always the same
to compare density, just lift minerals and whichever is heavier has more density
if you compare quarts and galena of the same size, galena will be 3x heavier
this only provides a rough measure of density
scientists use a balance or water displacement
Crystal Systems
crystals of each mineral grows by atom to make a crystal structure
these structures are based in 6 categories called the crystal systems.
halite is cubic
sometimes a mineral and crystal structure are the same
depending on how much space the crystal has, it can be formed perfectly or imperfectly
Cleavage and Fracture
the way a mineral breaks can identify it
a mineral that splits easily along flat surfaces has cleavage
this depends on crystal arrangement (depending how the atoms are arranged), it may break easily from some sides than others
mica breaks in sheets, feldspar splits at right angles
most minerals don't split evenly, therefore it is fracture
quartz has a curved shell-like fracture
metals form jagged points
Special Properties
some minerals glow under ultra-violent light, this is called fluorescence
Table of Contents
Properties of Minerals
Vocabulary
inorganic- the mineral can't come from an organismcrystal- the solid made up of atoms from an inorganic thing
element- something made up of one part of electrons, protons, and a nucleus
compound- parts of electrons and protons that are stuck together
Moh's Hardness Scale- something that puts minerals in places depending on their toughness
streak- the color of the particles left by rubbing the inorganic solid against a streak plate
luster- something that means how much the inorganic solid shines
cleavage- an inorganic organism that breaks in two on something smooth
fracture- how a inorganic organism appears when it splits in a weird form
fluorescence- an inorganic organism that shines below a super shining light
Outline
Intro
What is a Mineral
Identifying Minerals